Road expansion joint



SPt 20, 1938. R. R. ROBERTSON 2,130,859

ROAD ION JOINT Filed March C50, 1936 @055er E Ha/se rsa/V.

Patented Sept. v20, 1.938

UNITED STATES PATENT OFFICE The Translode Joint Company,

Chicago Heights, Ill.,va corporation of Illinois Application March 30,1936, Serial No. 71,572

11 Claims.

The present invention pertains to concrete construction joints and moreparticularly to a road expansion joint disposed between adjacentconcrete road slabs, with said joint including in combination anassembled core unit comprising superimposed precast mastic ller boardssep' arated by a transversely disposed load transmitting expansiondevice consisting of pairs of .core plates having portions thereofformed to slidably interiit one another with said core plates beingprovided with anchoring wings or arms adapted to be embedded in theadjacent concrete road slabs to reinforce the slabs and also serve as ameans whereby loads may be transmitted l5 from one -road slab across theexpansion joint to the adjacent 'road slab.

It is an object of this invention to provide an improved roadexpansion'joint mechanism comprising a preformed plastic core which isseparated into core sections by one or more sets ofI adjustable ortelescoping shield devices providing `pockets for the reception of thecore boards and also including anchoring wings or arms alternatelyarranged to be embedded in the concrete slabs on opposite sides of thejoint.

It is also an object of this invention to provide a road expansion jointforming device in the form of a unit adapted to be set up on a roadsubgrade for the separationof concrete road slabs, saiddevice-consisting of'an assembled preformed mastic core having core platescontacting opposite sides thereof with each of said core plates havingan intermediateportion thereof formed to provide double loops projectingin opposite directions from' y the plane of the plate and having one ofsaid with respect to those on the opposite side, saidA core plateshaving the middle portions thereof formed to provide double looped orS-sections adapted to sndabiy interni with the s or double 50 loopedportion of an opposite'core plate to provide a horizontal partitionextending transversely through the core.

It is furthermore an object of this invention to provide anexpansion'joint in the form of a core 55 board having portions thereofseparated by means ofa load transmission expansion device consisting ofoppositely positioned core plates having intermediate portions thereofformed .to provide double looped sections which interflt with the dublelooped sections of an opposite core plate to provide a quadruple platepartition separating sections of the core boards and adapted with theexpansion and contraction of the road slabs with the assistance ofanchoring blades or wings, forming part of the core plates and embeddedin the concrete in staggered relation on opposite sides of the coreboard, to serve as reinforcing means for `the sections of the concretedisposed adjacent the sides of the core board.

It is also an object of this invention to provide an expansion jointdevice for use between the concrete slabs of a road, said deviceconsisting of a compressible core having sections thereof separated byinteriitting S-sections forming integral parts of core plates -disposedon opposite sides of Vthe core and having struck therefrom anchoringblades which are embedded in the concrete slabs on opposite sides of thejoint.

It is an important object of this invention to provide a road expansionjoint mechanism for embeddingbetween concrete road slabs, said mechanismconsisting of one or more load transmission units each consisting ofcore plates having anchoring blades struck therefrom with the anchoringblades of one plate staggered with respect to those of an oppositeplate, said core plates furthermore having integral portions thereofformed to provide double looped sections projecting in oppositedirections from the plates and positioned to slidably interflt with thedouble looped portions of an opposite plate to provideA an expansionjoint partition inclosing compressible packings and affording a shieldacross the expansion joint to prevent water or foreign materials fromentering the main portion of the joint.

Other and further important objects of this invention will be apparentfrom the disclosures in the specification and the accompanying drawing.

The invention (in preferred forms) is illustrated in the drawing andhereinafter more fully described.

On the drawing:

Figure 1 is a vertical detailed section taken through an expansion jointembodying the principles of this invention and including core plateshaving double looped portions which interiit one another to form apartition across the core board for the transmission of loads across thejoint from one concrete slab to another-with the assistance of anchoringmembers struck froml the :core plates.

Figure 2 is a top plan view of the expansion joint load transmissionunit with the concrete omitted.

Figure 3 is a vertical detail section of a modied form of loadtransmitting expansion joint consisting of upper and lower loadtransmitting shield units engaging opposite sides of the core andprojecting therethrough and including staggered anchoring means whichare embedded in the concrete on opposite sides of the joint.

As shown on the drawing:

The road expansion joint as illustrated in Figures 1 and 2 is formed bymeans of the joint forming unit illustrated in Figure 2 before beingembedded between concrete road slabs.- The various members comprisingthe joint forming unit are adapted to be assembledland tied together andthen shipped to locations ready to be placed in position upon the roadsubgrade to permit concrete to be poured on opposite sides of the jointforming unit. The improved joint forming unit illustrated in Figures 1and 2 comprises a preformed compressible bottom filler board I and anupper illler board 2 constructed of asphalt, sponge rubber, cork or anyother suitable compressible material, such for example as thecompressible material known to the trade asFlexcel. 'Ihe two ller orcore boards I and 2 are disposed one above the other and are separatedand held in place by means of a load transmission device or unitcomprising a pair of oppositely positioned metal plates 3 havingapertures provided therein to register with apertures provided in thecore boards I and 2 to permit tie wires 4 to be projected through theplates and the core boards with the ends of the wires twisted upon oneanother as illustrated in Figures 1 and 2 to hold the core boards andthe load transmitting device in assembled relation ready to be shippedto location `ior installation upon a road subgrade between concrete roadslabs.

Each of the metal plates' 3 has the middle portion thereof bent over orformed to provide an intermediate S-section in the form of a wide loop 5and a narrow loop 8 respectively projecting away from opposite sides ofthe plate 3 with the looped ilanges integrally connected by means of acommon plate I formed by the integral connection of one of the sideplates of each of the looped flanges. As clearly illustrated in Figure lthe narrow looped flange 8 and the common plate 1 forming ya partthereof projects transversely of the core between the upper and lowercore boards I and 2 and slidably telescopes or projects into the widelooped iiange 5 of theopposite plate.

The two narrow looped flanges 6 project in op' posite directions throughthe core andin sliding contact with one another to provide a partitionbetween the lower and upper core boards I and 2 consisting of fourthicknesses of the metal plates. The plates 3 together with theinterfitting S-'sections thereof provide suitable holding pockets orsockets for the lower margin of the top core board 2 and for the uppermargin of the lower core board I. The two wide or larger looped ilanges5 of the plates 3 provide chambers in the closed ends of said loopedanges which are filled with a compressible material 8 such as oakumtreated with asphalt or the. like.

Struck from the upper margins of each of the plates 3 are taperedanchoring blades or wings 9 the outer ends of which are wider than theinner ends to serve as wedge or anchoring means when The loadtransmission device after being assembled as a unit as illustrated inFigure 2 isadapted to be shipped to location to be disposed transverselyacross the road vsubgrade and extending from the center'strip of theroad outwardly to the outer edge thereof. With the expansion jointdevice mounted in position concrete is deposited on opposite sides ofthe joint forming mechanism to embed the same and form the concrete roadslabs Ill. As clearly illustrated in Figure 1 both the anchoring blades9 and the large looped flanges 5 of the core plate are embedded in theconcrete forming the road slabs I0. The anchoring blades 9 not onlyserve as a means for anchoring the load transmission device in theadjacently positioned road slabs I to permit loads to be transmittedfrom one road slab through the core to the opposite road slab, but alsoserves as reinforcing means for reinforcing the concrete sectionsadjacent opposite sides of the upper portion of the joint and above thewide looped flanges of the load transmitting unit.

Figure 3 illustrates a modiied form o-f load expansion joint embeddedbetween concrete road slabs II and I2 and consisting of a compressiblecore comprising a lower filler or core board I3, an intermediateller orcore board I4 and an upper filler or core board I5. The three coreboards are sepa-rated by lower andupper load transmission devicessubstantially the same as that illustrated and described in connectionwith Figures 1 and 2 of the drawing with the exception that the lowerportions of the plates 3 have anchoring blades or wings 9 strucktherefrom in addition to the'upper anchoring blades struck from theupper margins of the core plates. The

upper and lower anchoring blades on each side of the joint are staggeredwith respect to one another as are also the blades on opposite sides ofthe joint. v

When a load is applied to the top of the road slab II the load istransmitted across the expansion joint through the load transmissiondevices connecting the two road slabs. Under normal conditions when aload is applied to one of the road slabs there is a tendency for theconcrete of the opposite road slab to crack along the dotted line I6Vand along the dotted line l1 of the lower portion of the road slab I.I.With the present form of load transmission unit forming part of theexpansion joint and embedded between the concrete road slabs II and I2the anchor blades 9 are` so positioned that they strengthen the normallyweakened sections of the road slabs by extending through the crackingareas thereby tending to defer the cracking of Iportions of the roadslabs when excessive loads are applied to the road. 4

It will of course be understood that various details of construction maybe varied through a wide range without departing from the principles ofthis invention and it is therefore not the -purpose to limit the patentgranted hereon otherwise than necessitated by the scope of the appendedclaims. Y

I claim as my invention:

l. In an expansion joint for embedding between adiacent concrete roadslabs, preformed compressible core boards, a load transmission deviceprojecting between the core boards and comprising a pair of platescontacting opposite sides of the core boards, double looped sectionsintegrally formed on said plates and slidably intertting one another toprovide a partitionbetween the core boards, a compressible packingbetween the-double looped sections of said plates, and anchoring bladeson said plates projecting outwardly from opposite sides of the joint andembedded in the concrete road slabs.

2. The combination with adjacent concrete road slabs having core memberstherebetween, of a load transmitting means anchored in the slabs onopposite sides of the core members and projecting therebetween, saidload transmitting means comprising a pair of plates each having av pairof looped sections formed therein and projecting from opposite sides ofthe plate with the looped sections of one plate slidably interfittingthe looped sections of the other plate.

3. The combination with adjacent concrete road slabs having core memberstherebetween,

of a load transmitting means anchored in the slabs on-opposite sides ofthe core members and projecting therebetween, said load transmittingmeans comprising a pair of plates each having a pair of looped sectionsformed therein and projecting from opposite sides of the platev with thelooped sections of one plate slidably interfitting the looped sectionsof the other plate, and staggered anchor blades on said plates embeddedin said slabs.

4. The combination with adjacent concrete road slabs having corevmembers therebetween, of a load transmitting means anchored in the slabson opposite sides of the core members and projecting therebetween, saidload transmitting means comprising a pair of plates each having a pairof looped sections formed therein and projecting from opposite sides ofthe plate with the looped sections of one plate slidably intertting thelooped sections of the other plate, staggered anchor blades struckoutwardly from said plates and embedded in said slabs, and acompressible filling disposed between the interiltting looped sectionsof said plates.

5. The combination with adjacent concrete road slabs having core memberstherebetween, of a load transmitting means anchored inr the slabs andprojecting between the core members,

said load transmitting means comprising a pair of metal plates, meansfor securing the plates on opposite sides of the core members, anchorblades struck from said plates and embedded in said slabs, said anchorblades of one plate staggered with respect to the anchor blades on theopposite plate, a. large loop and a small loop formed on each of saidplates and connected to one another by a common'plate projecting betweenthe core members, said small loop of each plate projecting between thecore members into the large loop of the opposite plate.

6. The combination with adjacent concrete road slabs having core memberstherebetween, of a load-transmitting means anchored in the slabs andprojecting between the core members, said load transmitting meanscomprising a pair of metal plates, means for securing the plates onopposite sides of the core members, anchor blades struck from saidplates and embedded in said slabs, said anchor blades of one platestaggered with respect to the anchor blades on the opposite plate, alarge loop and a small loop formed on each of said plates and connectedto one another by a common plate projecting between the core members,said small loop of each plate projecting between the core members intothe large loop of the opposite plate, and a filling in each of Saidlarge loops to serve as a seal between the large loop and the small loopprojecting therein.

7. The combination with adjacent concrete road slabs having a multiplesectioned joint core therebetween, of a load transmitting meansprojecting between the sections and .anchored in said road slabs, saidload transmitting means comprising a pair of metal plates each having anintermediate portion thereof formed to provide a wide loop and a narrowloop projecting in opposite directions and connected to one another withthe narrow loop projecting between the core sections and into the wideloop of the opposite plate.

8. A road expansion joint disposed between adjacent road slabs andcomprising superimposed plastic filler boards, metal plates positionedagainst opposite sides of said boards, anchor blades struck outwardlyfrom said plates, each of said plates having a portion thereof foldedupon itself to form a two loop section with one loop section anchored inone of the road slabs and the other loop section projecting through thejoint between the plastic ller boards and into the oth road slab.

9. A road expansion joint comprising superimposed preformed ller boards,metal plates on opposite' sides of said boards and overlapping the spacetherebetween, said plates folded to form looped portions projecting inopposite directions transversely between the ller boards with a loopedportion of one plate overlapping a looped portion of another plate toprovide four thicknesses of metal between the ller boards.

10. An expansion joint forming mechanismincluding in combination a loadtransmitting unit comprising a pair of plates, anchoring blades strucktherefrom, each of said plates having portions thereof deected outwardlyfrom opposite sides thereof to form looped anges connected by a commonplate section forming part of each of said looped flanges and projectingthrough the plane of the plate from which it is formed.

11. An expansion joint forming mechanism comprising a plurality ofpreformed solid plastic core boards, and means connecting the same andcomprising a pair of plates having interlltting 8- sections formedtherein and projecting transversely between said core boards and beyondboth sides thereof.

ROBERT R. ROBERTSON.

